Poly(arylene sulfide) polymers are engineering thermoplastics that have excellent heat resistance and are widely employed in various fields of applications. Some specialized applications require the polymers used therein to have certain qualities such as good surface smoothness and/or good metal adhesion. Poly(arylene sulfide) polymers produced by conventional methods do not have good surface smoothness and good metal adhesion and therefore are not commercially useful in applications requiring those qualities. It is known to use silica as a filler of a flow improver for poly(arylene sulfide) as disclosed in U.S. Pat. Nos. 4,247,598 and 4,395,512. However, the fillers heretofore known to be useful in combination with poly(arylene sulfide) do not impart improved surface smoothness or metal adhesion. In some applications that require good metal adhesion poly(arylene sulfide) can be used if the metal undergoes a separate step to pre-etch or base coat the metal, but this does not improve surface smoothness of the poly(arylene sulfide).
It would be beneficial if the surface smoothness and metal adhesion of poly(arylene sulfide) polymers could be improved without detrimentally affecting other physical properties.